In Part One of this article we looked at the physical, electronic and audio characteristics of great aviation headsets. Now, in Part Two, we will explore the world of national and international equipment certifications, the use of equipment in airside operations (as opposed to in-flight operations), and take a look at some outstanding audio equipment.

5. FAA Certifications and Standards

5.1 TSO (Technical Standard Order) Certification

Ensuring the headset has TSO certification is expected for aviation use. This certification guarantees that the headset meets the FAA’s rigorous standards for quality and safety, making it reliable for use in aircraft. Failure to meet FAA certifications can result in compromised safety, reduced performance, and potential regulatory penalties.

To make sure an aviation headset complies with the TSO (Technical Standard Order) certification, the following main criteria must be met:
+ Design and Performance Standards:
The headset must meet the performance specifications outlined in the applicable TSO standards. For aviation headsets, the relevant TSO is typically TSO-C139, which sets specific requirements for audio performance, noise attenuation, and compatibility with aircraft communication systems. This includes:
  – Clear communication quality: The headset must ensure no signal degradation when used in conjunction with aircraft communication systems.
  – Audio frequency response: The headset must provide the necessary audio fidelity for clear communication over radio systems.
  – Microphone sensitivity: The microphone must have a noise-cancelling feature that ensures clarity in high-noise environments such as cockpits.
+ Durability and Environmental Resistance:
Headsets must be able to withstand environmental factors typical in aviation operations. This includes:
  – Temperature tolerance: The headset should function across a wide range of temperatures, both at high altitudes and in ground-based heat.
  – Vibration and shock resistance: The headset should endure regular cockpit vibrations and potential physical shocks.
  – Moisture and dust protection: The design should resist moisture from sweat or cockpit humidity, as well as dust or dirt ingress.
+ Electrical Compatibility:
The headset must be compatible with the aircraft’s electrical and communication systems, ensuring it integrates seamlessly without causing interference. This includes:
  – Impedance matching: Proper impedance is necessary for clear audio signals and to prevent distortions when used with avionics.
  – Electrical shielding: The wiring and components must be shielded from electromagnetic interference (EMI) to ensure reliable operation.
+ Noise Reduction Standards:
For noise attenuation, the headset must meet the noise reduction standards specified under the TSO guidelines. The headset should provide:
  – Active Noise Reduction (ANR): ANR models must meet standards for noise-cancelling effectiveness in environments with high levels of cockpit noise.
  – Passive Noise Reduction (PNR): For PNR models, the physical construction of the earcups must block out a specified level of ambient noise.
+ Comfort and Ergonomic Design
While not strictly performance-based, the TSO requires that headsets be designed for long-term use without causing discomfort. This includes considerations like:
  – Weight: The headset must be lightweight enough for extended use without causing strain.
  – Adjustability: The design should allow for adjustment to fit different head sizes and shapes comfortably.
+ Battery Life and Power Management (For Wireless Models):
For wireless aviation headsets, the TSO certification includes criteria for reliable power management:
  – Battery life: The headset must have sufficient battery life to cover a long flight without interruption.
  – Power resilience: The battery must function reliably in varied temperature and environmental conditions, with no significant loss in performance.
+ FAA Documentation and Testing:
To be TSO-certified, the manufacturer must:
  – Submit the headset for rigorous testing by the FAA or an authorized certification body to ensure it meets the specific TSO-C139 criteria.
  – Provide detailed technical documentation and test reports to the FAA, showing compliance with the TSO performance standards.
These criteria ensure that an aviation headset meets the highest standards of safety, durability, and performance in the aviation environment, providing pilots and crew with the reliable communication equipment necessary for safe flight operations.

5.2  ETSO (European Technical Standard Order)

Aside from FAA certifications, pilots operating globally should also consider headsets that meet international standards, such as the ETSO (European Technical Standard Order) certification, to ensure compliance and safety across different regulatory jurisdictions.

The TSO and the ETSO are similar certification processes for aviation equipment, including headsets, but there are notable differences between the two, particularly regarding regulatory bodies, standards applied, and regional considerations. Here’s a comparison of the key differences:
+ Regulatory Authorities Compared:
  – TSO (Technical Standard Order):  Overseen by the Federal Aviation Administration (FAA) in the United States. The FAA governs the TSO process, ensuring that aviation products, including headsets, meet the safety and performance requirements outlined in the U.S. aviation regulatory framework.
  – ETSO (European Technical Standard Order): Regulated by the European Union Aviation Safety Agency (EASA) in Europe. ETSO certification ensures compliance with aviation safety standards across the EU member states and aligns with European regulatory policies.
+ Certification Standards and Reference Documents:
  – TSO Certification: TSO certifications are based on U.S. standards and requirements. For headsets, the specific TSO-C139 sets performance criteria, such as noise reduction, electrical compatibility, and environmental durability, as established by the FAA. Each TSO is assigned a unique code, like TSO-C139 for headsets, that defines the specific requirements for that equipment.
  – ETSO Certification: ETSO certification typically aligns with European standards but is often harmonized with global standards, including those from the FAA. While ETSO and TSO have many shared technical criteria, ETSO certifications may refer to different or additional European standards or documents. For instance, the relevant European specification may refer to EUROCAE standards (e.g., EUROCAE ED-14 for environmental testing), which may have slight variations compared to U.S.-based standards.
+ Scope and Application:
  – TSO: TSO certification applies to aviation equipment in the United States and in many other countries that recognize FAA standards. For products sold primarily in the U.S. or to operators using U.S.-registered aircraft, TSO certification is required to ensure compliance with FAA regulations.
  – ETSO: ETSO certification is specifically required for aviation products used in EU member states and countries that fall under EASA’s jurisdiction. It is mandatory for aviation equipment to meet ETSO standards if the product is intended for use in Europe or on EU-registered aircraft. In some cases, there may be additional European regulatory considerations beyond the scope of TSO standards.
+ Environmental Testing:
  – TSO: Environmental testing under TSO regulations follows the RTCA DO-160 standard, which specifies how aviation equipment should perform under different conditions such as temperature, humidity, vibration, and electromagnetic interference (EMI). TSO equipment must meet the specific environmental tolerance levels outlined by the FAA.
  – ETSO:  ETSO also follows the RTCA DO-160 environmental testing standards, but in some cases, EUROCAE standards may apply, depending on the equipment category. This slight variation in reference standards might lead to subtle differences in how tests are conducted or interpreted in different regions.
+ Cross-Recognition:
  – TSO: TSO certification is recognized by many global regulatory bodies outside the U.S., including in countries that follow FAA guidelines. However, ETSO certification may still be required for equipment used on aircraft registered in European countries.
  – ETSO: ETSO certification is accepted in Europe and recognized by certain other aviation authorities. However, aircraft registered in the U.S. or countries adhering to FAA regulations may still require TSO certification, meaning a dual certification might be necessary for headsets to be sold and used globally.
+ Documentation and Approval Process:
  – TSO: The FAA has a specific certification process for obtaining TSO approval. Manufacturers must submit test data, technical drawings, and performance reports demonstrating that the headset meets the FAA’s standards for communication and safety equipment.
  – ETSO: EASA requires a similar process, but the documentation and approval procedures may differ slightly, especially regarding the acceptance of certain performance data and technical documentation. The Application for ETSO Authorization can involve additional checks to ensure compliance with European aviation safety laws and directives.
+ Regional Focus:
  – TSO: TSO certification is primarily aimed at ensuring compliance within the U.S. aviation system, governed by FAA regulations. Products certified under TSO must meet the FAA’s standards for performance and safety.
  – ETSO: ETSO certification focuses on European safety and operational standards. While many of the technical requirements overlap with TSO, the focus is on compliance with EASA regulations and European-specific needs, such as compatibility with European air traffic control systems or avionics requirements.
And so, while the technical requirements for TSO and ETSO certifications are largely harmonized, with both adhering to similar performance and safety standards, the regulatory environment and approval processes differ. TSO certification is governed by the FAA in the U.S., while ETSO certification is regulated by EASA in Europe. Both ensure that aviation headsets meet stringent performance, environmental, and safety criteria, but depending on the market, manufacturers may need to obtain both certifications to ensure global compliance.

5.3 Compatibility with Aircraft Systems

One must ensure that the headset is compatible with the aircraft type in which it will be operating. Different aircraft, such as general aviation, commercial, or military planes, may require different headset specifications for optimal communication. Also, when considering compatibility, it’s important to note that some modern glass cockpit aircraft use digital audio systems. Headsets designed for these systems may incorporate digital interfaces that offer enhanced features and integration with the aircraft’s avionics. As aircraft systems and regulatory requirements continue to evolve, it’s important to choose a headset that can adapt to these changes and ensure continued safety and reliability.

6. Airside Operations

Thus far we’ve been talking about in-flight operations, which pertain to activities that take place while the aircraft is in the air. This involves navigation, communication with air traffic control, and maintaining passenger safety and comfort. It includes the responsibilities of the flight crew—such as the pilot and co-pilot navigating the aircraft—and cabin crew ensuring passenger safety and providing services like food and assistance during the flight.

One mustn’t forget airside operations, which refers to all activities that occur on the ground at an airport, particularly within the restricted areas beyond security and customs. This includes runways, taxiways, aprons, and other areas where aircraft are maneuvered, serviced, or parked. Airside operations encompass tasks like aircraft fueling, maintenance, baggage handling, ground support coordination, and emergency response, involving personnel such as ground handlers, air traffic controllers, and maintenance staff. These operations are critical for ensuring the smooth arrival, departure, and turnaround of aircraft.

Companies like Hytera manufacture various communications devices that can be adapted for use in aviation, primarily in roles that support communication needs for airside operations rather than in-flight cockpit communication. Their offerings include mission-critical radios, such as the MT680 Plus Mission Critical TETRA Mobile Radio and PT560H Mission Critical TETRA Portable Radio, which are commonly used by public safety and emergency response teams due to their reliability, advanced noise-canceling features, and rugged construction.

1. Hytera HM782 VHF 136–174, MHz 50 Watt 1024 Channel DMR Mobile Radio: This is Hytera’s new state-of-the-art device, providing an intuitive user interface, and gateway connectivity between radio and data networks. The HM782 can connect multiple radio sites, provide wireless data transmission, and support multiple simultaneous mode functions. It offers GPS and Bluetooth. The HM782 can be deployed Back-to-Back to enable communication between analog and digital radios, or radios with different frequencies. Multiple Hytera HM782 mobile radios can be connected to an Ethernet/IP network to provide a reliable and cost-effective method to connect remote radio sites and extend coverage areas. If a wired IP network is unavailable between two repeaters, two HM782 radios using different frequencies can provide a wireless link between the repeaters. The Clarity Transmission feature provides a wireless data path between remote network devices and a central network management station. Note: Cardinal Communications ( http://www.cardinalcomms.com ) carries the HM782 and other Hytera equipment.
2. Hytera MT680 Plus Mission Critical TETRA Mobile Radio: This device offers high RF output power and features compliance with military and IP standards, making it suitable for use in tough environments. It provides secure communications with end-to-end encryption and features like a 10-Watt RF power transmitter, making it useful for ground operations at airports or supporting teams involved in emergency airside operations. This type of communication reliability and durability would be beneficial for ground crews and logistics in aviation contexts but is not typically used by pilots in-flight due to cockpit-specific communication requirements.
3. Hytera PT560H and PT580H Plus Mission Critical TETRA Portable Radios: These portable radios are engineered for reliable use in harsh conditions. They come with noise-canceling technology and high audio output, suitable for use in environments like airports where external noise levels are significant. These radios are designed for use by ground personnel, emergency services, or other support functions that require secure and consistent communication. They have features like IP68-rated protection and high-powered designs, making them useful for workers who operate both indoors and outdoors, which can be essential for aircraft maintenance crews or airport security teams.
4. Hytera EHW06 Wireless Earpiece: This earpiece offers hands-free communication, ideal for personnel who need to move around freely without being restricted by cables. The wireless design enhances mobility, which is particularly useful in airside environments where workers may need to navigate around aircraft and other ground equipment. The earpiece is designed for comfort, allowing extended use during long shifts in the noisy airport environment.
5. EHN12-Ex Earset with on-MIC PTT (ATEX): This earpiece is specifically designed for use in hazardous environments, which might include certain areas of airport operations where exposure to fuel or other potentially flammable substances occurs. It features an on-MIC Push-To-Talk (PTT) function, allowing easy communication while keeping the user focused on their tasks. This makes it suitable for refueling or maintenance crews working close to aircraft fuel systems.

Hytera’s portable radios and their accessories, such as their noise-canceling headsets, are very effective for roles like airside ground communication and operational logistics where similar rugged and secure communication tools are needed.

Conclusion

A well-chosen headset can make all the difference in both comfort and safety during flight.
A great aviation headset combines advanced noise reduction, clear communication capabilities, comfort for long-term wear, and durable construction. Whether wired or wireless, it’s essential to choose a model that fits individual needs and meets FAA certifications to ensure safety and reliability. Pilots should explore their options, taking into consideration the specific demands of their cockpit environment.
Additionally, the field of aviation headsets continues to rapidly evolve, with manufacturers constantly pushing the boundaries of technology to enhance safety, comfort, and communication clarity for pilots. When choosing a headset, one must consider not just the immediate needs but also future compatibility with advancing aircraft systems and changing regulatory requirements. ■

Cardinal Communications is Ready to Help You

Cardinal Communications (http://cardinalcomms.com) wants you to explore our portfolio of high-quality headsets and other audio accessories to find the one that best suits your needs.